uint16_t a0 = (ops[0] & 0x000000000000FFFF) >> 0;
uint16_t a1 = (ops[0] & 0x00000000FFFF0000) >> 16;
uint16_t a2 = (ops[0] & 0x0000FFFF00000000) >> 32;
uint16_t a3 = (ops[0] & 0xFFFF000000000000) >> 48;
uint16_t b0 = (ops[1] & 0x000000000000FFFF) >> 0;
uint16_t b1 = (ops[1] & 0x00000000FFFF0000) >> 16;
uint16_t b2 = (ops[1] & 0x0000FFFF00000000) >> 32;
uint16_t b3 = (ops[1] & 0xFFFF000000000000) >> 48;

if (ops[2] == 0) {
  a0 *= b0;
  a1 *= b0;
  a2 *= b0;
  a3 *= b0;
} else if (ops[2] == 1) {
  a0 *= b1;
  a1 *= b1;
  a2 *= b1;
  a3 *= b1;
} else if (ops[2] == 2) {
  a0 *= b2;
  a1 *= b2;
  a2 *= b2;
  a3 *= b2;
} else {
  a0 *= b3;
  a1 *= b3;
  a2 *= b3;
  a3 *= b3;
}
uint64_t c0 = (uint64_t)(a0) << 0;
uint64_t c1 = (uint64_t)(a1) << 16;
uint64_t c2 = (uint64_t)(a2) << 32;
uint64_t c3 = (uint64_t)(a3) << 48;
return c0 | c1 | c2 | c3;
// return (uint64_t) _mm_mullo_pi16((__m64)ops[0], (__m64)ops[1]);
